Twister ring lubricant



United States Patent TWISTER RING LUBRICANT Arnold J. Morway, Clark,N.J., assignor to Esso Research and Engineering Company, a corporationof Delaware N0 Drawing. Application February 13, 1956 Serial No. 564,860

11 Claims. (Cl. 252-35) 'This invention relates to new and improvedlubricating compositions and to the method of preparing the same. Moreparticularly, the invention relates to a twister ring lubricant preparedby thickening petrolatum to a grease consistency with a mixture of metalsalts of low and intermediate molecular weight carboxylic acids.

This application is a continuation-in-part of S.N. 498,- 741, filedApril 1, 1955, and now US. Patent 2,863,847, for the same inventor.

Twister ring lubrication is a problem found in the textile manufacturingart where untwisted yarn is twisted and wound at high speeds upon spoolsfor use in weaving looms. In the twisting and winding operation two ormore yarns or piles are brought together and twisted into a singlestrand and then wound on a spool or bobbin, which is mounted on aspindle within a twister frame. The bobbin stands vertically within acircular metal ring called a twister ring mounted on the twister frame.Riding upon the twister ring and traveling freely on its circumferenceis the traveler, a looped metal member made of steel or bronze. In theprocess of twisting and winding, two or more yarns or piles pass throughthe loop of the traveler, are twisted by its rotational movement aroundthe twister ring, and are wound on the bobbin, rotating upon thespindle. The bobbin rotates at speeds in the neighborhood of 7,000r.p.m. or more, and the traveler moves around the twister ring at speedsalmost as great. Though the traveler weighs only a fraction of an ounce,it may develop several pounds of centrifugal force when operated at topspeeds.

It has now been found that twister ring lubricants having excellentlubrication characteristics can be prepared by thickening petrolatum toa grease consistency with a mixture of metal salts. The twister ringlubricants prepared in accordance with the invention are particularlycharacterized by desirable dropping point and consistency properties aswell as outstanding extreme pressure and wear resistant properties.

The petrolatum used in the formulation of the greases of the inventionmay be any of the white, cream, yellow or amber petrolatums havingmelting points Within the range of about 75 to 135 F. and A.S.T.M.consistencies of from about 160 to 275 mm./10. In the preferredembodiment of the invention, petrolatums having melting points withinthe range of about 110 to 135 F. and A.S.T.M. consistencies of about 200to 275 mm./ are used. In general, the finished twister ring lubricantsof the invention will contain about 70 to 95 weight percent, preferablyabout 75 .to 90 weight percent, petrolatum.

The metal salt mixtures contemplated in the invention comprise the metalsalts of low molecular weight monocarboxylic acids having from about 1to 3 carbon atoms per molecule and metal salts of intermediate colecularweight monocarboxylic acids having from about 7 to 10 carbon atoms permolecule. The relative amounts of the low and intermediate molecularweight carboxylic acids employed will be such as to result in PatentedJan. 26, 1960 or anhydrous metal salt mixtures may be employed tothicken the petrolatum, though the former are employed in the preferredembodiment of the invention. In general, the finished twister ringlubricants of the invention will contain about 5 to 30 weight percent,preferably about 10 to 25 weight percent, of the hydrous mixture ofmetal salts.

The low molecular weight carboxylic acids useful in this inventioninclude saturated and unsaturated, aliphatic monocarboxylic acids havingfrom about 1 to 3 carbon atoms per molecule such as formic, acetic,propionic, acrylic and lactic acids. Acetic acid is especiallypreferred. Mixed low molecular weight carboxylic acids wherein the acidscontain from about 1 to 3 carbon atoms and have an averagesaponification value of above about 540 may also be employed.

For the purposes of this invention, those aliphatic monocarboxylic acidswhich contain from about 7 to 10 carbon atoms, preferably about 8 to 9carbon atoms, per molecule and which are intermediate in chain lengthand molecular weight when compared to the low molecular weight and highmolecular weight carboxylic acids are designated as intermediatemolecular weight carboxylic acids. Either saturated or unsaturatedintermediate molecular weight carboxylic acids may be utilized, thoughthe saturated fatty acids are-preferred. Straight chain or substantiallystraight chain acids are also preferred. vThe average saponification ofthe single or mixed intermediate molecular weight monocarboxylic acidsshould be about 310 to 440, preferably about 350 to 420. Some of theintermediate molecular weight monocarboxylic acids, within the aboveprescriptions, are exemplified by:

5-methyl-2-hexanoic Heptanoic (enanthic) Octanoic (caprylic) 2-ethylhexanoic C oxo acids Nonanoic (pelargonic) Decanoic (capric) C oxo acidsCommercial mixtures of these intermediate molecular weight carboxylicacids having an average saponification value of from about 310 to 440can also be employed.

The oxo acids useful for the purposes of the present invention, e.g. thesaturated branched chain C and C oxo acids, can be prepared by means ofthe well known oxo synthesis. This process involves the oxonation orcarbonylation of olefins with carbon monoxide and hydrogen attemperatures of about 300 to 400 F. and pressures of about 2500 to 4000p.s.i.g. in the presence of a group V'III metal catalyst, preferablycobalt. In US. Patent No. 2,632,021 the oxo process and the nature ofthe reaction products, e.g. the C oxo products, are disclosed in detail.The preparation of oxo acids from the oxo reaction products is describedin US. Patent No. 2,537,577 and US. Patent No. 2,553,364. Neither thepreparation of the oxo reaction products nor the preparations of oxoacids therefrom are considered to be directly related to the essence ofthe present instability at high temperatures and under mechanical stressto the lubricating compositions of the invention even without the use ofconventional extreme pressure additivcs and stabilizing agents. Othermetals useful for the purposes of this invention include the alkalimetals, i.e. sodium, potassium and lithium and the heavy metals ofgroups LII, IV and VIII of the periodic system. The heavy metals usefulfor the purposes of this invention include copper, zinc, lead, cobalt,strontium and maguesium.

The metal components of the salts of the low and intermediate molecularweight carboxylic acids may be any one or more of the metals set forthabove. In most cases, however, the low and intermediate molecular weightcarboxylic acid salts contain the same metal component.

In general, the lubricating compositions of the invention are preparedby heating the desired petrolatum to a temperature just above itsmelting point, i.e. at a temperature of about 130 to 140 F. Thesaponifying agent, e.g. lime, is then added to the melted petrolatum andthoroughly dispersed. A blend of the desired low and intermediatemolecular weight carboxylic acids is then added to the fluid dispersionwith continued stirring and without the application of further externalheating. The heat of reaction raises the temperature of the resultingmixture to about 170 to 200 F. The stirring is continued until thetemperature has subsided, and the grease mixture is then cooled. Thegrease may be finished by being subjected to high rates of shear in theorder of about 50,000 to 500,000 reciprocal seconds in such milling orhomogenizing devices as a Morehouse mill, Charlotte mill, ink mill,Manton-Gaulin homogenizer, etc. Where it is desirable, conventionallubricating grease additives may be added to the grease prior tohomogenization. These conventional additives are employed in amounts ofabout 0.01 to by weight and include such additives as oxidationinhibitors, corrosion and rust inhibitors, metal deactivators and thelike.

As noted above, the cold sett method of manufacture is preferred. Thismethod of employing relatively low temperatures results in the formationof hydrous mixtures of the metal salts of low and intermediate molecularweight monocarboxylic acids and avoids the possibility of effectingchanges in the color of the petrolatum due to heating at elevatedtemperatures. If desired, however, excellent twister ring lubricants mayalso be prepared by dehydrating the compositions at temperatures aboveabout 210 F. for a period of time sufficient to remove the water whichmay be present in the mixture. The amount of water present in thehydrous mixtures of metal salts can vary widely. In general, however,the amount of water present will be about 0.5 to 15.0 wt. percent,preferably about 1 to 5 wt. percent, based on the total weight of thehydrous mixture of metal salts.

The hydrous mixture of metal salts may also be prepared by separatelypreforming at least a portion of the low molecular Weight carboxylicacid salt and/or the intermediate molecular weight carboxylic acid salt.This method is especially useful when difierent metals are employed asbases for the salt constituents. Preformed metal salts can replace about30 to 80% of the free acids and stoichiometrically equivalent amounts ofthe bases.

The invention Will be more fully understood by reference to thefollowing specific examples illustrating various modifications of theinvention.

EXAMPLE I Four petrolatum based compositions thickened with hydrousmixtures of the metal salts of acetic acid and commercial caprylic acidhaving the formulations and properties set forth below in Table I wereprepared as follows:

Greases A and B.The petrolatum was charged to a grease kettle equippedwith efiicient stirring paddles. The petrolatum was melted by heating itto a temperature of about 120-125 F. The lime was then added andthoroughly dispersed. Without further external heating a blend of theacetic acid and the commercial caprylic acid was added to the meltedpetrolatum. The heat of reaction raised the temperature to above about175 F., and stirring was continued until the temperature had subsided.The grease was then cooled and homogenized in a Morehouse mill at about150,000 reciprocal seconds.

Grease C'.-This grease was prepared similar to greases A and B asdescribed above, except that the petrolatum was not melted and thehomogenization step was omitted.

Grease D.This grease was prepared similar to greases A and B.

Table I Compositions F'ormulaton (percent Wt):

Glacial Acetic Acid,

Light Amber Petrolaturn 4 Mol ratio acetic acid to commercial caprylicacid radicals Properties:

Appearance Pentration, 77 F Worked, 60 strokes Dropping Point, F

Shell 4 Ball Wear Test (1,800 r.p.m.,

10 kg. load, 75 0., 1 hr.) Spot diameter, mm

5. 8/1 5.8/1 Smooth, uniform greases below 120 1 Sap. No. 327; molecularweight 172. Drew Wecoline AAC; 2 Melting point F.; A.S.T.M. consistency265. lvlelting point 1l5l125 F.; A.S.T.M. consistency-210.

4 Melting point ll25 F.; A.S.T.M. consisteucy-2l0.

Theabove data show that excellent lubricants having characteristics thatmake them especially desirablei'as twister ring lubricants can beprepared in accordance with the teachings of this invention. Morespecifically, the data show lubricants having built in extreme pressureand high dropping point properties can be obtained by the dispersion ofrelatively small amounts of hydrous mixtures of alkaline earth metalsalts of low and intermediate molecular weight carboxylic acids.

The data further show that when especially low percentages of the metalsalts are employed, as in greases C and D, eifective lubricatingcompositions can only be achieved by melting the petrolatum andfinishing the lubricant by homogenization (see grease D).

To further show the advantages afiorded by the lubricant compositionsprepared in accordance with the invention, the following data clearlydemonstrate the improved wear resistant properties achieved bythickening the desired petrolatum with hydrous mixtures of alkalineearth metal salts of low and intermediate molecular weightmonocarboxylic acids.

Comparative tests of the extreme pressure properties of lubricantcompositions previously employed by the art and the lubricants of theinvention were run on a four-ball extreme pressure tester. Three bronzeballs and 1 steel ball were employed under the standard conditions of2.5 kilogram load, 1800 r.p.m., 75 C. for half an hour. See Boner,Manufacture and Application of Lubricating Greases (Reinhold PublishingCorp., New York, 1954), pages 867 to 869, for a detailed description ofthis test. The data obtained are set forth in the table below;

Table 11 FOUR-BALL WEAR TEST DATA Scar diameter, mm. (1) Grease B (TableI) 0.23

3. The composition of claim 1 wherein said metal constituents arealkaline earth metals.

4. The composition of claim 1 wherein said low molecular weightcarboxylic acid is acetic acid.

(2) Mixed base Sodium ca1cium Soap thickened 5 5. The composition ofclaim 1 wherein said intermepetmlatum 0 58 diate molecular weightcarboxylic acid is caprylic acid. (3) gg T E Z; g g 030 6. A twisterring lubricant composition comprising a 13 1 th 1 h 1 1 t f 18 000 to 90000 major amount of petrolatum and about to weight prepfied gt l lg liilsuisf a W 0 d 10 percent of a hydrous mixture of calcium acetate andcal- In an actual operation wherein twister rings were cium caprylate inwhich the mol ratio of acetic acid to lubricated with grease B,representative of the inventive Capryhc acld. radlcals 1S m the range ofabout 5:1 composition, and polyethylene thickened petrolatum, de 3011-scribed in Table II above, the following results were The cofnposltlon0136131111 6 wherein Sald petrolatum bt i d; 15 has a droppmg pointwithin the range of about 110 to Table III Hrs. in No. of Gross Wt. WtJLossinWtJ Wt. Loss/ Lubricant 0pera- Travel- (gms. of Traveler TravelerTraveler/ tion ers 9 Travelers) 5.) (gms.) Hour (1) Polyethylenethickened petrola- {(new) 144 986553 0. 6851 1 144 192 127.2600 0. 66280. 0223 1. s 10- (2) Grease B (Table I) {(uew) 51 30. 1830 0. 5918 348182 100.7212 0. 5863 0. 0045 1.3 10- 1 Described in Table II. 5Bronzetravelers.

The data in the above table shows that the twister ring lubricant of theinvention reduced the traveler wear to one tenth of that resulting fromthe use of a conventional twister ring lubricant in an actual threadtwisting operation.

In brief summary, it has been found that efiective twister ringlubricants can be prepared by thickening petrolatum to a greaseconsistency by a cold sett method with hydrous mixtures of metal saltsof low molecular weight monocarboxylic acids having from about 1 to 3carbon atoms per molecule and intermediate molecular weightmonocarboxylic acids having from about 7 to 10 carbon atoms permolecule. At least some and usually all water of reaction remains in thelubricating compositron.

The invention is not limited to the specific conditions and materials ofthe foregoing examples. These conditions and materials may be variedwithin the limits indicated in the general portions of thespecification.

What is claimed is:

1. A twister ring lubricant composition comprising a major amount ofpetrolatum and 5 to weight percent of a hydrous mixture of metal saltsof low molecular weight carboxylic acids having from about 1 to 3 carbonatoms per molecule and intermediate molecular weight carboxylic acidshaving from about 7 to 10 carbon atoms per molecule and wherein themolar ratio of low to intermediate molecular weight acid salts in saidhydrous mixture is about 2:1 to about :1.

2. The composition of claim 1 wherein said petrolatum has a droppingpoint within the range of about 75 to 135 F. and an A.S.T.M. consistencyof about 160 to 275 mm./10.

F. and an A.S.T.M. consistency of about 200 to 275 mm./ 10.

8. A method for preparing a twister ring lubricant compositioncontaining 5 to 30 weight percent of a mixture of metal salts whichcomprises melting a major proportion of petrolatum, dispersing a metalbase in said melted petrolatum, adding to said dispersion a blend of lowmolecular weight carboxylic acids having from about 1 to 3 carbon atomsper molecule and intermediate molecular weight carboxylic acids havingfrom about 7 to 10 carbon atoms per molecule and then cooling to obtainsaid lubricant composition, said metal base being present in sufiicientamounts to saponify said acids and said molar ratio of low tointermediate molecular weight acid is about 2:1 to 40:1.

9. The method of claim 8 wherein said metal base is an alkaline earthmetal base.

10. The method of claim 8 wherein said low molecular weight carboXylicacid is acetic acid and the intermediate molecular weight carboxylicacid is caprylic acid.

11. The method of claim 8 wherein said lubricant composition is finishedby being homogenized at high rate of shear within the range of about50,000 to 500,000 reciprocal seconds.

References Cited in the file of this patent UNITED STATES PATENTS2,274,675 Earle Mar. 3, 1942 2,393,797 Morgan Jan. 29, 1946 2,457,586McGrogan Dec. 28, 1948 2,604,452 Morway et al July 22, 1952 2,735,815Morway et a1. Feb. 21, 1956

1. A TWISTER RING LUBRICANT COMPOSITION COMPRISING A MAJOR AMOUNT OFPETROLATUM AND 5 TO 30 WEIGHT PERCENT OF A HYDROUS MIXTURE OF METALSALTS OF LOW MOLECULAR WEIGHT CARBOXYLIC ACIDS HAVING FROM 1 TO 3 CARBONATOMS PER MOLECULE AND INTERMEDIATE MOLECULAR WEIGHT CARBOXYLIC ACIDSHAVING FROM ABOUT 7 TO 10 CARBON ATOMS PER MOLECULE AND WHEREIN THEMOLAR RATIO OF LOW TO INTERMEDIATE MOLECULAR WEIGHT ACID SALTS IN SAIDHYDROUS MIXTURE IS ABOUT 2:1 TO ABOUT 40:1.